/*
 * @Author: chen haoxuan
 * @Date: 2021-05-13 08:24:49
 * @LastEditTime: 2021-05-13 08:35:23
 */
// 友元成员函数
// friend 函数不仅可以是一般函数(非成员函数),而且可以是另一个类中对的成员函数
#include<iostream>
using namespace std;
class Date; // 对Date类的提前声明
class Time
{
    public:
        Time(int,int,int);
        void display(Date &);
    private:
        int hour;
        int minute;
        int sec;
};
class Date
{
    public:
        Date(int,int,int);
        friend void Time::display(Date &);
    private:
        int month;
        int day;
        int year;
};
Time::Time(int h,int m,int s)
{
    hour=h;
    minute=m;
    sec=s;
}
void Time::display(Date &d)
{
    cout<<d.month<<"/"<<d.day<<"/"<<d.year<<endl;
    cout<<hour<<":"<<minute<<":"<<sec<<endl;
}
Date::Date(int m,int d,int y)
{
    month=m;
    day=d;
    year=y;
}
int main()
{
    Time t1(10,13,56);
    Date d1(12,25,2004);
    t1.display(d1);
    system("pause");
}